Hall-Effect switch devices are well known to those skilled in the art. Such devices normally include: a voltage regulator; a sensing element effective to sense disruption of magnetic field flux and changes in intensity of a magnetic field; an amplifier operative to amplify a signal provided by the sensing element, and; a switch member, such as a thyristor, operative to actuate and provide an output signal when the magnetic field flux in predetermined proximity to the sensing element is disrupted by a predetermined amount and when the magnetic field intensity to which the sensing element is exposed is increased above a value predetermined for actuating the switch member.
As such, Hall-Effect switch devices can be advantageously used to provide an output signal that can be received and processed by processing means such as a micro-processor well known to those skilled in the art operative to provide information relative the position of the component in response to a selected one of conditions: (a) disruption by a predetermined amount of a magnetic field of a magnet secured to the switch device in response to the component including a ferrous material thereupon having been moved into predetermined proximity to the sensing element; (b) exposure of the sensing element to a magnetic field above a predetermined amount provided by a magnet secured to the component having a magnetic field intensity that increases in a direction theretowards that has been moved by the component into predetermined proximity to the sensing element; (c) disruption by a predetermined amount of a magnetic field of a magnet secured to the switch device in response to an irregularity in the surface of the component having been moved by the component thereacross in predetermined proximity to the sensing element; (d) exposure to a magnetic field intensity above a predetermined amount provided by a magnet having a magnetic field intensity that increases in a direction theretowards that has been moved by the component into predetermined proximity to the sensing element, and; (e) disruption by a predetermined amount of a magnetic field of a magnet secured to the switch device in response to the component being made from a ferrous material and having an irregularity in the surface thereof having been moved across the magnetic field in predetermined proximity to the sensing element.
Hall-Effect switch devices are available from many commercial sources and have been miniaturized to the point where they are contained on a single silicon chip and are commercially available with sensing elements responsive to different levels of magnetic field intensity.
Hall-Effect switch devices are characteristically electrically grounded and powered by a constant-voltage power source that is connected by means of an electrical conductor to a singular power input terminal on the device. The devices also characteristically feature a singular output terminal to which an electrical conductor is connected for conveying the switch member output signal to the means for processing the signal and providing information therefrom previously described.
Characteristically the power sources and means for processing the output signal have been located remotely from the device often mandating the necessity and expense in having to make long runs of both the power input and output signal conductors as well as including a ground wire in instances when the device is electrically grounded remotely therefrom.
In contrast to the above, the instant invention provides a system utilizing such Hall-Effect switch devices in conjunction with an electrical circuit whereby the output signal terminal is connected to the power input conductor in close proximity to the device and the effect of the output signal upon the power input conductor is monitored and processed by the processing means thereby eliminating the need for long runs of two conductors and often eliminating the ground wire where the device is electrically grounded remotely therefrom. Such is particularly advantageous where the movable component is a vehicular transmission shift rail and the power source is a battery located on the vehicle remotely therefrom.
Additionally, in conjunction with conditions (d) previously described, a problem has characteristically heretofore existed in insuring accurate movement of the magnet towards and away from the sensing element which is addressed herein by including a resilient biasing means, such as a coiled spring, and at least one movable member in an open-ended bore provided in the device that are collectively operative to accurately control movement of the magnet towards and away from the sensing element in response to movement of the component.